The Payload Flattener

A medium Python interview practice problem on DataDriven. Write and execute real python code with instant grading.

Domain

Python

Difficulty

medium

Seniority

L3

Problem

Given a nested dict (keys map to primitive values OR to inner dicts), return a flat dict whose keys are the joined key paths using the given separator. Non-dict values become leaves with the full joined key path.

Summary

Turn a deeply nested API response into a flat row.

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